Heatrae Sadia MegaLife HE Series User manual

MEGAFLO HE
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36 00 5843 Iss 1

2
2
Contents
SECTION PAGE
1 INTRODUCTION ........................................................................... 3
2 GENERAL REQUIREMENTS ...................................................... 4
3 INSTALLATION - GENERAL ......................................................... 5
4 INSTALLATION - DIRECT UNITS ................................................. 8
5 INSTALLATION - INDIRECT UNITS ............................................. 10
6 COMMISSIONING ....................................................................... 14
7 USER INSTRUCTIONS................................................................ 15
8 MAINTENANCE ........................................................................... 16
9 FAULT FINDING & SERVICING .................................................. 17
10 DIMENSIONS & SPECIFICATIONS ........................................... 20
11 GUARANTEE ................................................................................ 23
12 CONTACTS ................................................................................... 24
Contents
Please read and understand these instructions before starting work.
Please leave this leaflet with the user following installation

MEGAFLO HE
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1
Congratulations on your purchase of a Heatrae Sadia MegaLife cistern fed vented water heater.
The MegaLife is manufactured in the UK from top quality materials and meets all the latest
relevant safety and constructional standards. The high grade Duplex stainless steel cylinder
offers exceptional strength and corrosion resistance which is backed by a 25 year guarantee.
Its performance and insulation levels meet the latest requirements of Building Regulation Part L.
The MegaLife vented water heater must be fed from a cold water feed cistern located above the
water heater and hot outlets to be served. The unit must have a suitable vent pipe installed on
the outlet that is arranged to discharge over the cold water feed cistern.
Direct units are supplied with either one or two electric immersion heaters (depending on model)
which incorporate an adjustable thermostat and an over-temperature thermal cut-out.
Indirect units are supplied fitted with a thermostat and over-temperature thermal cut-out for the
control of the primary heat input to the MegaLife from the boiler.All indirect models are also
supplied with one electric immersion heater for use as an auxiliary heat source should the
primary heat source be switched off.
Introduction
Introduction

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4
IMPORTANT : PLEASE READ AND UNDERSTAND THESE INSTRUCTIONS BEFORE INSTALL-
ING THE MEGALIFE WATER HEATER. INCORRECT INSTALLATION MAY INVALIDATE
GUARANTEE.
THE MEGALIFE MUST BE INSTALLED BY A COMPETENT INSTALLER IN ACCORDANCE
WITH ALL RELEVANT REGUALTIONS AND CODES OF PRACTISE IN FORCE AT THE TIME
OF INSTALLATION.
THE MEGALIFE MUST BE FED FROM A COLD WATER FEED CISTERN. A SUITABLE VENT
PIPE MUST BE INSTALLED.
2.1 SITING THE MEGALIFE (see Diagram 1)
The MegaLife range of water heaters must only be installed as a CISTERN FED VENTED unit
supplied from a cold water feed cistern at an appropriate head height above the heater and outlet
points. Ensure that the feed cistern height above the heater does not exceed its maximum rated
pressure of 40 metres (4 bar). The feed cistern should comply with the requirements of Schedule 2
Section 7 Paragraph 16: Cold Water Services to the Water Supply (Water Fittings) Regulations
1999 (previously Water Byelaw 30).
A vent pipe MUST be connected to the outlet of the heater. This must rise continuously and be
arranged to discharge into the feed cistern. The vent pipe must have a minimum bore diameter of
19mm.
DO NOT connect directly to the mains water supply.
DO NOT connect any pressure relief device or other valves to the vent pipe of this heater.
DO NOT install in a position where the heater is liable to be subject to frost conditions.
The MegaLife unit must be vertically floor mounted or on a suitable plinth. It can be placed anywhere
convenient provided the vent pipe can be correctly installed. Ensure that the floor or supporting plinth
is of sufficient strength to support the “full” weight of the unit (refer to Tables 3 and 4 on page 21 for
unit weights). Ideally the heater should be sited close to the point where hot water is required most
frequently. Pipe runs should be kept as short as possible for maximum economy. Access to
associated plumbing connections, immersion heaters and indirect controls should be possible for
servicing and maintenance of the system.
2.2 OUTLET/TERMINAL FITTINGS (TAPS, ETC.)
The MegaLife can be used in conjunction with most types of terminal fittings. In a cistern fed system
the pressure at the outlet fittings is due to the head height of the cold water feed cistern above the
outlet point. When choosing suitable fittings ensure they will operate at the pressure available at the
outlet point.
2General Requirements
General Requirements

MEGAFLO HE
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Installation - General
3Installation - General
3.1 PIPE FITTINGS
As all the pipes to the MegaLife are of stainless steel brazing or soldering is difficult, therefore use
22mm COMPRESSION FITTINGS when connecting to the MegaLife pipes.
“Push fit” type fittings MUST NOT BE USED for direct connection to the MegaLife pipes, however
they may be used elsewhere in the system if technically suitable.
If solder type fittings are used in the supply pipework to the MegaLife the pipework should be
thoroughly flushed to remove any flux residue.
3.2 COLD WATER SUPPLY
A 22mm cold water supply is recommended from the cold water feed cistern. No other connection
should be taken from this supply. A servicing valve or stop valve with a fixed washer plate should
be incorpoarted in a convennient and accessible position in the cold feed pipe. The cold feed pipe
should be connected to the heater connection marked INLET.
3.3 DRAIN TAP
A suitable draining tap should be installed at the lowest point of the cold feed pipe between the cold
water service valve and the heater to facilitate draining the heater.
3.4 OUTLET PIPEWORK
The outlet pipework should be connected to the heater connection marked OUTLET. The vent pipe
must be teed into the outlet pipe (see section 3.5 below). Outlets above the heater can be teed off the
vent pipe. Ideally the pipework from the heater to the outlet fittings should be in 22mm pipe with short
runs of 15mm pipe to the terminal fittings.
3.5 VENT PIPE
A vent pipe MUST be connected to the outlet of the heater.
The vent pipe must rise continuously and be arranged to discharge into the cold water feed cistern.
The vent pipe must have a minimum bore diameter of 19mm.
No valves should be fitted to the vent pipe. It is not acceptable to replace the vent pipe with a
pressure relief device.
The hot water distributing pipes can be teed off the vent pipe. If fitting a shower booster pump
particualr attention should be made to the manufacturers instructions regarding the positioning of the hot
water tapping to prevent air entrainment via the vent pipe.

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Installation - General
Diagram 1 - Schematic installation details
OUTLET/
VENT
INLET
STOP
VALVE
COLD
MAINS
SUPPLY
VENT
PIPE
CISTERN
TAN K
MEGALIFE
HEATER
DRAIN
MAX. HEAD
40 m

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Diagram 2 - Secondary circulation connection to cold feed pipe
3.6 SECONDARY CIRCULATION
A 3/4” BSP female threaded boss is provided (supplied blanked with a 3/4” BSP plug and sealing
washer) for the connection of a secondary circulation return pipe. Alternatively, if it is a requirement
that the whole cylinder contents be circulated the secondary return can be teed into the cold feed
pipe via a swept tee joint (available as an accessory, order code no. 95 605 812).
A suitable WRAS approved bronze circulation pump and check valve to prevent backflow should
be installed in the secondary return pipework.
Secondary circulation is not recommended for direct electric units.
COLD
SUPPLY
COLD INLET
CONNECTION
CHECK
VALVE
SECONDARY
RETURN
SECONDARY
CIRCULATION
PUMP
SWEPT
TEE

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Installation - Direct units
4Installation - Direct units
4.1 FITTING THE IMMERSION HEATER(S)
The immersion heater(s) supplied should be screwed into the 1 3/4” BSP boss(es) on the side of the
MegaLife unit. Ensure the “o”-ring seal is in place and is not damaged. DO NOT use any other
type of seal or sealant on the threads.
The MegaLife heater will not accept standard 2 1/4” BSP threaded immersion heaters. This is to
prevent the use of immersion heaters which do not have a safety thermal cut-out fitted. The
immersion heater should only be replaced with authorised Heatrae Sadia spare parts.
The 170 litre and 210 litre direct models are supplied with two immersion heaters. If both immersion
heaters are not required a boss can be plugged with the aid of an 1 3/4” BSP blanking plug
available from Heatrae Sadia (order Heatrae Sadia part no. 95 605 829).
4.2 WIRING (see Diagram 3)
All electrical wiring should be carried out by a competent electrician and be in accordance with the
latest I.E.E. Wiring Regulations. Each circuit must be protected by a suitable fuse and double pole
isolating switch with a contact separation of at least 3mm in both poles.
The immersion heater(s) should be wired in accordance with Diagram 3 and the instructions supplied
within the cap of the immersion heater(s).The immersion heater(s) MUST be earthed. The supply
cable must be routed through the cable grip provided and the outer sheath of the cable firmly secured
by tightening the screws on the cable grip. Replace the immersion heater cover(s) before operating.
DO NOT operate the immersion heater(s) until the MegaLife has been filled with water.
4.3 OPERATION
It is recommended that the immersion heater thermostats are set to between position 4 and 5 (60o-
65oC), however they can be set between 1 and 5 (10o and 70oC). The thermostat incorporates a
thermal cut-out that will switch off the immersion heater in the event of a thermostat failure. The
thermal cut-out reset button position is indicated on Diagram 3. DO NOT bypass the thermal cut-out
in any circumstances.
4.4 SAFETY
DO NOT BYPASS THE THERMAL CUT-OUT(S) IN ANY CIRCUMSTANCES
DISCONNECT FROM THE MAINS SUPPLY BEFORE REMOVING ANY COVERS
NEVER ATTEMPT TO REPLACE AN IMMERSION HEATER OTHER THAN WITH THE
RECOMMENDED HEATRAE SADIA MEGALIFE SPARE PART

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Diagram 3 - Immersion heater schematic wiring diagram

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Installation - Indirect units
5Installation - Indirect units
5.1 BOILER SELECTION
The MegaLife Indirect models are suitable for use with most gas or oil fired boilers. The boiler used
can either be a sealed system or open vented type. The maximum primary circuit pressure is 3.5
bar. If an open vented type boiler is used it must be fed from a separate boiler feed and expansion
cistern, it MUST NOT be fed from the MegaLife cold water feed cistern.
The primary flow from the boiler should be pumped. Gravity circulation is not recommended due to its
reduced heating performance. It is recommended that an air bleed point or automatic air vent is
incorporated in the primary return pipework close to the MegaLife unit to aid in bleeding air from the
primary heating coil.
The boiler should be fitted with adequate thermal control. This will normally include a primary flow
thermostat and a safety over temperature cut-out. The boiler flow temperature should usually be set to
82oC (maximum flow temperature to primary heat exchanger 90oC).
The boiler cannot be vented through the MegaLife unit.
5.2 INDIRECT THERMAL CONTROLS
Control of the storage temperature when indirectly heated is provided by the cylinder thermostat fitted.
The control is located under the grey plastic cover located between the indirect coil connections. The
cylinder thermostat is adjustable between 10oand 70oC, adjustment is made by rotating the
adjustment dial located under the control cover. Recommended storage temperature is 60oto 65oC.
See Diagram 4.
5.3 WIRING
All electrical wiring should be carried out by a competent electrician and be in accordance with the
latest I.E.E. Wiring Regulations.
The MegaLife Indirect Thermostat and Thermal Cut-out are factory pre-wired. It is recommended that
these controls are wired in series with a suitable 2 or 3 port motorised valve to control the primary
flow through the heater coil. Wiring to external controls is made via the terminal block fitted. The cable
should be routed through the aperture in the terminal cover and secured using the cable grip provided.
The Indirect Thermal Cut-out MUST NOT be bypassed.
5.4 HEATING SYSTEM CONTROLS
The controls provided with the MegaLife will ensure the safe operation of the MegaLife within a central
heating system. Other controls will be necessary to control the space heating requirements and times
that the system is required to function. Depending on the boiler selected, heating circuit design and
controls used it may be beneficial to incorporate a system bypass in the heating system pipework.
The Megaflo is compatible with most heating controls, examples of electrical circuits are given in
Diagrams 5 and 6. However, other systems may be suitable, refer to the controls manufactur-
ers’ instructions, supplied with the controls selected, for alternative system wiring
schemes.

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5.5 IMMERSION HEATER
The MegaLife indirect units are supplied with an immersion heater which can be used as an alternative
heat source should the boiler supply need to be isolated from the MegaLife unit. Refer to Sections 4.1
to 4.4 and Diagram 3 for details of fitting, wiring and operation of the immersion heater.
Diagram 4 - Indirect controls housing details

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CONTROL TERMINAL NUMBERING MAY DIFFER FROM THOSE SHOWN. REFER TO INSTRUCTIONS SUPPLIED WITH CONTROLS SELECTED
N.B. A DOUBLE POLE ISOLATING SWITCH MUST BE INSTALLED IN THE MAINS SUPPLY
FUSED (3 AMP) MAINS SUPPLY
JUNCTION BOX (NOT SUPPLIED)
KEY
B r BROWN B l BLUE G GREY O ORANGE GY GREEN/YELLOW DHW DOMESTIC HOT WATER HTG HEATING
NOTES 1. ALL EARTH CONNECTIONS MUST BE LINKED BACK TO THE MAINS EARTH SUPPLY 2. ASSUMES BASIC BOILER WITH EXTERNAL PUMP 3. THE ABOVE DIAGRAM IS FOR GUIDANCE ONLY, HEATRAE SADIA ACCEPT NO LIABILITY FOR ANY LOSS OR DAMAGE ARISING FROM ANY ERRORS OR OMISSIONS THAT MAY BE INADVERTENTLY CONTAINED WITHIN THIS DIAGRAM. THE VARIOUS EQUIPMENT MANUFACTURERS SHOULD BE CONSULTED TO CONFIRM THE CORRECT OPERATION OF THEIR PRODUCTS WITHIN THE SYSTEM
Diagram 5 - 2 x 2 port valve system
Installation - Indirect units
PROGRAMMER
BOILER
ROOM STAT
DHW
ZONE VALVE

ZONE VALVE (HTG)
12345678910
LN
LN G
Br Bl O
GY
G
Br Bl O
GY

132 
2
HTG 
DHW 


ON ON
13
LN 
L
N
PUMP
MEGALIFE INDIRECT
THERMAL CONTROLS
(SUPPLIED FITTED)

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CONTROL TERMINAL NUMBERING MAY DIFFER FROM THOSE SHOWN. REFER TO INSTRUCTIONS SUPPLIED WITH CONTROLS SELECTED
FUSED (3 AMP) MAINS SUPPLY
KEY
B r BROWN B l BLUE G GREY O ORANGE GY GREEN/YELLOW W WHITE DHW DOMESTIC HOT WATER HTG HEATING
N.B. A DOUBLE POLE ISOLATING SWITCH MUST BE INSTALLED IN THE MAINS SUPPLY
NOTES
1. ALL EARTH CONNECTIONS MUST BE LINKED BACK TO THE MAINS EARTH SUPPLY 2. ASSUMES BASIC BOILER WITH EXTERNAL PUMP 3. THE ABOVE DIAGRAM IS FOR GUIDANCE ONLY, HEATRAE SADIA ACCEPT NO LIABILITY FOR ANY LOSS OR DAMAGE ARISING FROM ANY ERRORS OR OMISSIONS THAT MAY BE INADVERTENTLY CONTAINED WITHIN THIS DIAGRAM. THE VARIOUS EQUIPMENT MANUFACTURERS SHOULD BE CONSULTED TO CONFIRM THE CORRECT OPERATION OF THEIR PRODUCTS WITHIN THE SYSTEM
JUNCTION BOX (NOT SUPPLIED)
Diagram 6 - 3 port mid-position valve system
PROGRAMMER
BOILER
ROOM STAT 3 PORT MID POSITION
VALVE
12345678910
LN
G
WBl O
GY

132 
2

13
LN

L
N
PUMP
MEGALIFE INDIRECT
THERMAL CONTROLS
(SUPPLIED FITTED)
LN HTG

DHW 

ON ON
DHW OFF

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Commissioning
6Commissioning
6.1 FILLING THE MEGALIFE WITH WATER
Ensure that all fittings and immersion heater(s) are correctly fitted and tightened.
i) Open the highest hot tap in the system.
ii) Open the mains cold water supply to the cold water feed cistern.
iii) Open the service valve or stop valve fitted in the cold feed pipe to the unit. Allow the unit to fill.
When water issues from the hot tap allow to run for a few minutes to flush through any dirt or
swarf, then close tap.
iv) Allow cold water feed cistern to fill to the water line.Adjust the float valve if necessary.
v) Open successive hot taps to purge any air from the system.
vi) Check all connections for leaks and rectify as necessary.
6.2 DIRECT UNITS
DO NOT switch on the electrical supply until the MegaLife unit is filled with water.
When the system is full switch on the electrical supply to the immersion heater(s) and allow the unit
to heat up. Check that the thermostat operates correctly.Astorage temperature of approx. 60oC is
recommended (between graduations 4 and 5 on the thermostat). If necessary the temperature can be
adjusted by inserting a flat bladed screwdriver in the adjustment knob on top of the immersion heater
thermostat and rotating (see Diagram 3). The adjustment range 1 to 5 represents a temperature range
of between 10oand 70oC.
6.3 INDIRECT UNITS
Fill the indirect (primary) circuit following the boiler manufacturer’s commissioning instructions. To
ensure the primary heating coil in the Megaflo is filled any motorised valve fitted to control the primary
flow to the MegaLife primary heating coil should be manually opened by moving the lever on the
motor housing to the MAN OPEN setting. When the primary circuit is full return the lever to the
AUTO position. Vent any trapped air by opening the air bleed.
DO NOT switch on the boiler until the MegaLife unit is filled with water.
When the system is full switch on the boiler, ensure the programmer is set to Domestic Hot Water.
Allow the MegaLife unit to heat up and check that the indirect thermostat and any motorised valve
connected operate correctly. Astorage temperature of approx. 60oC is recommended . If necessary
the temperature can be adjusted by rotating the adjustment knob (located on the front of the thermostat
mounting bracket see Diagram 4).
6.5 BENCHMARKTM COMMISSIONING CERTIFICATE
On completion of the installation and commissioning procedures detailed in this manual the Bench-
mark TM “Vented Cylinder Commissioning Certificate” should be completed and signed off by the
competent installer or commissioning engineer in the relevant sections.
The various system features, location of system controls, user instructions and what to do in the
event of a system failure should be explained to the customer. The Commissioning Certificate should
be left with the customer along with these instructions.

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User Instructions
7User Instructions
7.1 TEMPERATURE CONTROL
IMMERSION HEATER(S)
Acombined thermostat and thermal cut-out is provided for each immersion heater. The thermostat is
factory set to give a water storage temperature of approx. 60oC, however it can be set to control
between 10oC and 70oC. This will usually have been done during installation. Adjustments can only
be made by opening the terminal cover(s), DO NOT remove the cover(s) without first switching
off the electrical supply. The temperature adjustment is made by inserting a flat bladed screwdriver
in the slot in the disc on top of the thermostat and rotating (see Diagram 3).
If in any doubt consult a competent electrician.
INDIRECT UNITS
Indirect units are fitted with an Indirect Thermostat which will control either a 2 or 3 Port motorised
valve and hence the temperature of the water in the MegaLife unit. The thermostat is factory set to
give a water storage temperature of approx. 60oC, however it can be set to control between 10oC
and 70oC, this will usually have been done during installation. Adjustments can only be made by
opening the terminal cover. DO NOT remove the cover without first switching off the electrical
supply. Temperature adjustment is made by roating the adjustment knob located on the front of the
thermostat mounting bracket (see Diagram 4).
If in any doubt consult a competent electrician.
DO NOT bypass the thermal cut-out in any circumstances.
7.2 FLOW PERFORMANCE
As with any cistern fed vented system the pressure obtained at the outlet points is due to the height
(head) of the cold water feed cistern above the outlet. Outlet points with a low head may give lower
flow rates than those located at a lower level within the property. When several hot outlets are opened
simultaneously some loss of flow from outlets with a low head or located some distance from the
MegaLife may occur. This is a function of the system design and does not necessarily indicate a fault
with the water heater.
If in doubt consult a competent plumbing installation engineer.

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Maintenance
8Maintenance
8.1 MAINTENANCE REQUIREMENTS
The MegaLife has been designed and manufactured to require very little maintenance. However, to
ensure the continued optimum performance of the MegaLife it should be periodically maintained. This
is of particular importance in hard water areas where limescale can build up on hot surfaces and
eventually affect the heating efficiency of either the immersion heater(s) or primary heating coil.
Maintenance should be carried out by a competent person and any replacement parts used should be
authorised Heatrae Sadia MegaLife spare parts.
In hard water areas consideration should be given to periodically descaling the immersion heater
elements. To do this the MegaLife unit will need to be drained, 8.2 and 8.3 below detail how to drain
the unit and remove the immersion heater(s).
8.2 DRAINING THE MEGALIFE UNIT
Switch off the electrical supply to the immersion heater(s) and shut down the boiler on
indirect units. Turn off the cold water supply to the MegaLife unit by shutting the service valve in
the cold water feed pipe from the feed cistern. Attach a hosepipe to the drain cock having sufficient
length to take water to a suitable discharge point below the level of the unit, at least one metre below
the unit is recommended. Open drain cock.
8.3 DESCALING IMMERSION HEATER(S)
Open the cover(s) to the immersion heater(s) and disconnect wiring from immersion heater(s). Un-
screw immersion heater(s) using an immersion heater box spanner.
Carefully remove any scale from the surface of the element(s). DO NOT use a sharp implement as
damage to the element surface could be caused. Ensure sealing surfaces are clean and seals are
undamaged, if in doubt fit a new ‘o’-ring seal.
Replace immersion heater(s) and tighten using an immerion heater box spanner.
Rewire the immersion heater(s) in accordance with Diagram 3. Close and secure terminal cover(s).
8.4 REFILLING SYSTEM
DO NOT switch on the immersion heater(s) or boiler until the system has been completely refilled.
Close the drain tap. With the highest hot tap in the system open, turn on the service valve in the cold
water feed pipe. When water flows from the hot tap allow to flow for a short while to purge air and to
flush through any disturbed particles. Close hot tap and then open successive hot taps in system to
purge any air. The electrical supply can now be switched on.

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Fault Finding & Servicing
Fault Finding & Servicing
9
9.1 IMPORTANT
i) Servicing should only be carried by competent installers in the installation and maintenance of
water heating systems.
ii) Any spare parts used MUST be authorised Heatrae Sadia parts.
iii) Disconnect the electrical supply before removing any electrical equipment covers.
iv) NEVER bypass any thermal controls or operate system without the necessary safety
controls.
v) Water contained in the MegaLife unit may be very hot, especially following a thermal control
failure. Caution must be taken when drawing water from the unit.
9.2 SPARE PARTS
Afull range of spare parts are available for the MegaLife range. Refer to the Technical Data label on the
unit to identify the model installed and ensure the correct part is ordered.
Description Part no.
Immersion heater 95 606 794
Immersion heater ‘o’-ring 95 611 810
Immersion heater combined thermostat and
thermal cut-out 95 612 599
Indirect units only:
Indirect thermostat 95 612 597
Indirect thermal cut-out 95 612 598
9.3 FAULT FINDING
The Fault Finding chart overleaf (Table 1) will enable operational faults to be identified and their possible
causes rectified. Any work carried out on the MegaLife water heater and its associated controls MUST
be carried out by a competent installer for water heating systems. In case of doubt contact the Heatrae
Sadia Service Department (see Section 12).

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Fault Finding & Servicing
Table 1 - Fault Finding Chart
FAULT POSSIBLE CAUSE REMED
Y
No hot water flow 1. No water in cold feed
cistern
1. Check water supply to cold
feed cistern
2. Service valve in cold water
feed pipe from cistern turned
off
2. Turn on service valve
3. Air lock in system 3. Check pipework layout for
possible air locking points, rectify
as necessar
y
4. Inadequate head between
outlet and cold water feed
cistern
4. Check minimum head
requirement of outlet fitting
Hot water flow gradually
decreases
1. Outlet flow rate exceeds
inlet flow to cold water feed
cistern
1. Install higher flow float valve.
Consider larger cold water
cistern stora
g
e capacit
y
2. Flow starvation caused by
opening further outlets
2. Check pipe sizings and layout.
Consider restricting flow rate
throu
g
h lower taps
Water from hot taps is
cold
1. DIRECT immersion heater
not switched on
1. Check and switch on
2. DIRECT immersion heater
thermal cut-out has operated
2. Check. Reset by pushing
button. (See Diagram 6)
3. INDIRECT programmer
set to Central Heatin
g
onl
y
3. Check. Set to a Domestic Hot
Water pro
g
ramme
4. INDIRECT boiler not
working
4. Check boiler operation. If fault
is suspected consult boiler
manufacturer's instructions
5. INDIRECT thermal cut-out
has operated
5. Check. Reset by pushing
button on cut-out. Check
operation of indirect thermostat
6. INDIRECT motorised
valve not connected correctly
6. Check wiring and/or plumbing
connections to motorised valve
(see Diagrams 9&10)

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20
20
Dimensions & Specifications
Dimensions & Specifications10
Diagram 7 - Dimensions
B
C
D
160 160
195
50
OUTLET
SECONDARY
RETURN
INLET
PRIMARY
FLOW
PRIMARY
RETURN
22.5
O
45
O
33.75
O
PLAN VIEW
530 DIA
IMMERSION
HEATER(S)
INDIRECT
THERMAL
CONTROLS